Comparative study on the main components and antioxidant activity of Scutellaria baicalensis in different authentic regions
Scutellaria baicalensis comes from the dried roots of Scutellaria baicalensis Georgi, a perennial herbaceous plant in the family Lamiaceae. It is also known as mountain tea root or earth gold tea root and is a commonly used traditional Chinese medicine. It was first recorded in the “Shennong Bencao Jing”. Scutellaria baicalensis has various physiological activities such as antibacterial, anti fatigue, anti-tumor, antioxidant, anti-inflammatory, and liver protection, which are closely related to the flavonoid components in Scutellaria baicalensis, such as baicalin, baicalin, baicalein, and baicalein.
Authentic medicinal materials refer to medicinal materials that have been selected through long-term clinical application of traditional Chinese medicine, produced in specific regions through specific production processes, with better quality and efficacy than the same type of medicinal materials produced in other regions, and have a higher reputation. According to herbal records, the quality of Scutellaria baicalensis produced in Yizhou, Hubei, Fuzhou, Shaanxi, Jing County, Gansu, and Yanzhou, Shandong is relatively good. Ecological changes, such as climate and soil factors, are the most significant factors leading to the transformation of land areas and the formation of land quality. Rehe Scutellaria baicalensis from Chengde, Hebei has always been recognized as a high-quality and effective authentic Scutellaria baicalensis. However, due to excessive excavation of Scutellaria baicalensis medicinal materials in the Chengde authentic production area, it is currently difficult to buy authentic Scutellaria baicalensis from Chengde, Hebei in major and medium-sized medicinal markets across the country. At present, Shandong has many planting bases for Scutellaria baicalensis, with high yields and good quality, gradually becoming a modern authentic production area for Scutellaria baicalensis. At present, no comparative study has been conducted on the quality and efficacy of Scutellaria baicalensis from different authentic regions. Therefore, based on the characteristics of “excellent quality and good efficacy” of authentic medicinal materials, this article evaluates whether there are differences in the quality and antioxidant activity of Scutellaria baicalensis from different authentic regions from multiple perspectives of “chemical composition activity”, in order to provide experimental support for measuring whether the quality of Scutellaria baicalensis from different authentic regions is equivalent.

It is difficult to comprehensively and objectively reflect the integrity and complexity of traditional Chinese medicine components through single or multiple indicator content determination. The chemical fingerprint of traditional Chinese medicine is a comprehensive characterization of the chemical composition information of traditional Chinese medicine and an important means of quality control for Chinese medicinal materials. Although the fingerprint spectrum of traditional Chinese medicine can reflect the overall characteristics of its chemical components, the components it reflects are not related to the efficacy of the medicine, and there are still limitations. Antioxidants play an important role in the treatment of various chronic diseases such as cancer and cardiovascular diseases, as well as various age-related diseases. Traditional Chinese Medicine (TCM) spectrum and efficacy analysis is the process of pattern recognition of TCM fingerprint information and its pharmacological effects, clarifying the relationship and contribution between the two, in order to achieve a comprehensive evaluation of TCM quality and efficacy. There are currently few literature reports on the spectral effects of Scutellaria baicalensis. Xu et al. and Jia et al. established a correlation study between the fingerprint spectra and anti-inflammatory activity of Scutellaria baicalensis and Scutellaria baicalensis; Pang et al. conducted spectral analysis on the anti-aging effects of chemical components in the roots, stems, and leaves of Scutellaria baicalensis; Scholars have also linked the fingerprint spectrum of Scutellaria baicalensis with its anti-inflammatory, antipyretic, and anti influenza virus effects to clarify its pharmacological substance basis. So far, no one has used spectral correlation to explore whether there are differences in the quality of Scutellaria baicalensis from different authentic regions. To this end, this project established an ultra high performance liquid chromatography (UPLC) fingerprint evaluation method for Scutellaria baicalensis, combined with similarity evaluation and orthogonal partial least squares discriminant analysis (OPLS-DA) to improve the quality evaluation system of Scutellaria baicalensis from different regions; We investigated its ability to scavenge DPPH, ABTS, and O2- free radicals, and further conducted spectral correlation studies using bivariate correlation analysis.
This study investigated the separation performance of the Acquity UPLC BEH C18 (2.1mm × 50mm, 1.7 μ m) chromatographic column and the Acquity UPLC HSS T3 (2.1mm × 100mm, 1.8 μ m) chromatographic column. It was found that the Acquity UPLC HSS T3 (2.1mm × 100mm, 1.8 μ m) chromatographic column had better separation efficiency and more peaks; We also investigated different mobile phase systems such as methanol water, acetonitrile water, methanol-0.1% formic acid water, acetonitrile-0.1% formic acid water, and 0.1% formic acid water-0.1% formic acid acetonitrile, with different column temperatures (30, 35, 40 ° C), injection volumes (1, 2 μ L), detection wavelengths (254, 280nm), and elution gradients. The optimal chromatographic conditions were ultimately determined as mobile phase 0.1% formic acid water -0.1% formic acid acetonitrile, column temperature 35 ° C, volumetric flow rate 1 μ L, and detection wavelength 280nm.
This study also investigated the extraction methods (ultrasound, reflux), solvent concentrations (30%, 50%, 70%, 90% ethanol), and extraction times (10, 30, 60, 90 minutes) of the test solution. The results showed that using 70% methanol as the extraction solvent and ultrasonic extraction for 60 minutes, the peak areas of the common peaks in the Scutellaria baicalensis sample solution were higher and the peak shapes were better.
This study used UPLC technology to establish a fingerprint of Scutellaria baicalensis, which has good precision, stability, and repeatability, and can be used for quality evaluation of Scutellaria baicalensis. The similarity between the 25 batches of Scutellaria baicalensis from Laiwu, Shandong and Chengde, Hebei and the control fingerprint spectrum is above 0.983, indicating that there is no significant difference in the chemical composition of Scutellaria baicalensis between Laiwu, Shandong and Chengde, Hebei. Through OPLS-DA analysis, it was found that baicalin, quercetin A-7-O – β – D-glucuronide, and baicalein may be differential markers affecting the quality of Scutellaria baicalensis in Laiwu, Shandong and Chengde, Hebei. The box plot results showed that the peak areas of these three components in Scutellaria baicalensis in Laiwu, Shandong were higher than those in Chengde, Hebei. Li et al. and Yang et al. found that the chemical composition content of Scutellaria baicalensis in Chengde, Hebei was lower than that in other production areas (such as Shandong), which is consistent with the results of this study. Scutellaria baicalensis from two real estate areas have strong DP-PH, ABTS, and O2- radical scavenging abilities, with Shandong Laiwu Scutellaria baicalensis having better antioxidant capacity than Hebei Chengde Scutellaria baicalensis. Further using the OPLS-DA model, two real estate areas can be distinguished based on three antioxidant indicators. Through bivariate correlation analysis, we found that the scavenging ability of Scutellaria baicalensis towards DPPH, ABTS, and O-radicals is significantly positively correlated with various flavonoids and flavonoid glycosides in Scutellaria baicalensis, and promotes antioxidant activity; Only one component (5,7-dihydroxy-2 ‘- methoxyflavone-7-O-glucuronic acid) showed a significant negative correlation and inhibited antioxidant activity.
In summary, it can be seen that Scutellaria baicalensis from Laiwu production area in Shandong Province is superior to Scutellaria baicalensis from Chengde area in Hebei Province in terms of chemical composition and antioxidant capacity, and there are certain differences between the two in terms of composition and antioxidant capacity. However, given the small sample size of this study, further research is needed to increase the sample size, and further studies will be conducted on the impact of soil and climate factors on the quality formation of Scutellaria baicalensis in different production areas. From the perspective of ecological factors, the root causes of the differences in Scutellaria baicalensis quality in different production areas will be explained; In addition, research on various pharmacological effects such as anti-inflammatory, antiviral, and antibacterial should be strengthened to provide research strategies for comprehensively explaining whether there are differences in the quality and efficacy of Scutellaria baicalensis from different regions, and further enrich the scientific connotation of authentic research on traditional Chinese medicine materials. At the same time, it is necessary to strengthen the research on the regional adaptability characteristics of Scutellaria baicalensis medicinal materials, select planting sites reasonably, optimize planting techniques, establish scientific and reasonable quality evaluation standards for authentic medicinal materials, produce high-quality authentic medicinal materials, and better apply them to the traditional Chinese medicine industry